I. Field of the Invention
The instant invention relates to fill valves with floats, and, in particular, to toilet tank fill assembly having a float and a pilot operated fill valve.
II. Description of the Prior Art
Toilet tank fill valves with ballcocks are well known and in common usage. However, the conventional valve assemblies have suffered from several disadvantages, including noise, clogging of the diaphragm valve due to foreign bodies, unwieldy design due to the presence of a conventional ballcock, and sluggish action of conventional ballcocks. Prior known toilet fill valves may employ a ball float depending from an actuator arm or a float reciprocally mounted to the mounting tube for actuation of the fill valve when the fluid level drops below a predetermined level. As the water level reaches a full position, the buoyancy of the float will cause the fill valve to shut off. It is desirable for the valve to fill the reservoir as quickly as possible by maintaining a near maximum fluid flow until shut off of the valve.
In order to accommodate different tank sizes, particularly tank depths, the fill valves are provided with means for adjusting the position of the valve and/or flat. Early fill valves merely adjusted the angle of the actuator arm associated with the ball float. However, such assemblies do not accommodate the position of the fill valve in different tanks. More recently, fill assemblies have been provided with adjustable fill tubes to optimize the position of the fill valve for proper height and to prevent back siphoning through the valve. However, these adjustment assemblies have been found to be awkward and clumsy, in some instances, requires removal from the tank to adjust the length of the standpipe.
The present invention overcomes the disadvantages of the prior known reservoir fill assemblies by providing an efficient fill valve for filling the tank and incorporating a pilot operated valve for efficient operation.
The invention relates to a diaphragm water level control valve with a float for use in tanks such as flush tanks for toilets. The valve is mounted on the upper end of a vertical standpipe through which flush water is supplied. An outlet or discharge tube surrounds the standpipe and is concentric therewith. The diaphragm valve member is disposed at the top or upper end of the standpipe and functions to open and close the water inlet passage in the standpipe. The diaphragm valve member is disposed in a housing and together with the housing defines a vent valve chamber above the diaphragm.
The top wall of the housing has a vent port with a pilot valve disposed in the pilot valve chamber for opening and closing the vent port. The pilot valve includes a valve head which engages a valve seat to seal the vent port, and a stem portion which extends axially through said vent port.
A float member is generally an inverted cup shape and is slidably mounted on the discharge pipe. The float is linked to a stem actuator member which is pivotally mounted on the housing. When the water level in the tank drops, as for example when the toilet is flushed, the float member drops and the pilot valve member is unseated from the pilot aperture. The pilot valve is displaced and the vent port opened allowing the water pressure at the inlet tube to open the diaphragm valve. When the water level in the tank rises it will carry the float with it. The stem actuator member then disengages the stem, and the pilot valve is axially displaced to close the vent port.
The fill valve assembly is also provided with means for adjusting the length of the standpipe to accommodate different tank depths. The standpipe includes mating inlet and outlet tubes which direct water to the fill valve and into the tank, respectively. The fixed outlet tube incorporates a plurality of discrete camming grooves defining the positions of adjustment. The slidable outlet tube has a set of slots adapted to receive a flexible locking clip which selectively engages the camming grooves of the fixed tube to lock the slidable tube relative to the fixed tube. The locking clip is movable between a retracted position allowing adjustment of the standpipe and an inserted position preventing movement. The adjustment assembly provides convenient adjustment yet positive locking against movement.